I'm experiencing this too. My findings: it is not OS dependent (also happens with Windows 7), it is not browser dependent (Opera, Chrome/Chromium, Firefox), it doesn't matter if I connect via my router or the modem (PPPoE), I tried different DNS w/o luck. One page that fails quite often for me is bugzilla.gnome.org - all in all: this doesn't look like an Ubuntu problem. :-|
–
htorqueOct 30 '10 at 22:54

6 Answers
6

The reason for this is because your browser is not loading the stylesheet, which is hosted on another domain. Possible reasons could be due to the stylesheet domain being blocked or because your browser is failing to get DNS resolution for it.

Because that is a problem that happens on Mozilla sites. For instance, is common for users with ipv6 enable to not being able to install extensions and I have already seen css issues as well.
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lovinglinuxOct 30 '10 at 0:27

That domain doesn't have AAAA records in DNS, so that shouldn't give problems...
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JanCOct 30 '10 at 4:36

@lovinglinux turning off ipv6 in about:config didn't helped me, I also have a windows on the same computer and it works there (in case this could help), using latest ubuntu 10.10
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OmuOct 30 '10 at 21:51

You could try to set up a new Firefox profile for testing reasons. First, make sure all instances of Firefox are closed! It might take some time for the process to end even though Firefox is not visible any more.
If the commands below do not work make sure Firefox is closed by typing the following in a shell.

killall firefox-bin

Then run the Firefox Profile Manager. You can do that by entering the following command from a shell or by pressing Alt+F2 and entering it there:

firefox -profilemanager

You can setup a new profile there and try if it works with that fresh one. Be aware that the newly created profile will be set as new default. Do switch back to your original profile you have to start the profile manager again and select to start the appropriate profile.

If just read lovinglinux's answer and just wanted to let you know that - in case you tried to solve the issue with a new profile - you should get the same problem again, as setting up a new profile also uses the default about:config settings which are to use ipv6 by default (network.dns.disableIPv6=False). If the new profile solved your problems we have to search somewhere else for the problem. See MozillaZine for details on the option.